Mike Pelfrey has been pitching through forearm tendinitis, spotted yesterday by an MRI exam. The big righty says he gets tendinitis all the time, just not in his arm, and is convinced he’ll make his next scheduled start Sunday at home against the Brewers. Jerry Manuel, on the other hand, is not so sure.

“We all felt Mike didn’t have his best stuff and Mike is one of those guys that’s a very tough individual,” Manuel said, referring to Pelfrey’s first two starts this season. “He’ll go out there with foot broke and think everything is OK. So we have to do what we have to do. We’ll determine whether this start is in jeopardy or not. Right now we have not made that decision.”

When asked if it was premature that Pelfrey — 0-1 with a bloated 8.10 ERA in two subpar starts — said he could go Sunday, Manuel said “That’s Mike; if his arm is broken he’ll still think he can go out there and do what he needs to do. But we have to take our time with this and make sure that everything is OK, that we’re doing the right thing by him and by the team.”

Manuel said finding the problem was a relief for Pelfrey and the team, making his early struggles more easily explainable.

Manuel also said if Pelfrey — who started on anti-inflammatories today — can’t make his scheduled start Sunday, the Mets would be more inclined to call a starter up from the minors rather than shuffle their rotation or extend somebody out of the bullpen.